geophys (version 1.4-1)

dofry: Fry Estimation

Description

Calculate the Fry diagram for estimating shear on random point patterns

Usage

dofry(x, y, PLOT = FALSE)

Arguments

x

x-coordinates

y

y-coordinates

PLOT

logical, TRUE=plot

Value

List:

X

x-coordinates

Y

y

mx

mean X

my

mean Y

Details

The number of points returned can be large and plotting can take a long time, so when plotting can restrict the points by using plotfry.

References

Fry, N., (1979) <http://dx.doi.org/10.1016/0040-1951(79)90135-5> Random point distributions and strain measurement in rocks Tectonophysics, 60:89-105.

See Also

Showfry, plotfry, xtractlip

Examples

# NOT RUN {
RDAT = randFRY(400, LIM=c(0,0, 200, 200) , rlen=5   )
length(RDAT$x)
plot(RDAT$x, RDAT$y, asp=1, pch=".", cex=2)
flag = sqrt( (RDAT$x-mean(RDAT$x))^2  + (RDAT$y-mean(RDAT$y))^2)<75

DAT = list(x=RDAT$x[flag], y=RDAT$y[flag])
 x = DAT$x
    y = DAT$y
 plot(x,y, asp=1, pch=21, col='red', bg='gold', ann=FALSE, axes=FALSE)

FF = dofry(DAT$x, DAT$y )
AF = plotfry(FF, dis=30)

Z = xtractlip(AF)

lines(cluster::predict.ellipsoid(Z$hull), col='red')  
   




# }